overdiagnose

To diagnose something more often than it actually occurs.

Health experts deny claims that they overdiagnose mental health conditions.

Dissociative identity disorder is a contentious diagnosis: some professionals say the disorder is overdiagnosed; others say it doesn't even exist.

To diagnose as a clinical case what is truly a subclinical case.

Her GP incorrectly referred her to a pulmonologist, overdiagnosing what was clearly a case of subclinical, mild allergy.